1. Field of the Invention
The disclosure relates to cleaning apparatus and detecting method, and in particular relates to an auto-cleaning device and detecting method.
2. Description of the Related Art
Particles detection technology is currently being used in traditional vacuum cleaners, air cleaners, self-propelled vacuum cleaners, and clean rooms. The detection of amount of particles and environmental control is to make cleaning more efficient. With a simple and effective way to measure the amount of dust and the size, the cleaning performed by the traditional vacuum cleaners, air cleaners, or self-propelled vacuum cleaners can be more efficient, and thus it can promote environment protection by energy-saving and carbon emission reduction.
Known particle detection technology can be broadly divided into the following three categories:
(1) Optical detection: The main principle is to use a pair of optical transmitter and receiver devices, where each receiver detects intensity of light emitted by the corresponding optical transmitter. In principle, the detected intensity increases when the density of dust grains declines, thereby identifying the amount of dust present. For example, in U.S. Pat. No. 4,601,082, optical sensors are used to detect dust. Further, in U.S. Pat. No. 5,608,944 and U.S. Pat. No. 6,571,422, circuits of signal processing, such as amplification, filtering, and other methods, are introduced to improve the sensor's sensitivity.(2) Pressure-Difference detection: The principle determines whether the filter needs to be replaced or the amount of waste dust collection box is full by comparing the pressure difference between the dust collection box and the suction inlet.(3) Piezoelectric pressure sensing: The PZT (Lead Zirconate Titanate) pressure sensing element is placed at the inner wall of the vacuum suction inlet. The amount of dust inhaled is determined by the pressures applied to the PZT pressure sensing element by the impact of dust.